Of course, if you have a Pilen with brakes also in the can, you actually need TWO 15 mm spanners, which is just as unhelpful when you have a multitool with only one on it...I'm sure you don't need to ask how I discovered this either
Just remember to have a 15mm spanner in your saddlebag so you don't find yourself miles from home with no means of removing the wheel. Don't ask me how I know that. "the what tools for a fixie?" thread has a link to a nice spanner that fits easily into a bag.
But it is just about possible to repair 5 punctures at once on a Pompetamine without removing the wheel, DNAMHIKT either.
Oh, and two things: Don't assume the BB7s will be set up properly, mine were not. The two important evaluations for the BB7 are (1) does it spin freely without the brake on and (2) does it stop when you want. Might sound obvious, but the intial fettle will teach you a lot about them. You will find two things (1) That caliper bolt on the rear is not easy to get to at all, but is important (2) Each time you adjust the rear wheel, you alter the caliper adjustment. Not sure whether you need to but I adjust at the same time each time. The caliper/pad centering thing to start with is the key to getting a perfect system. The cable system has quite a bit of stretch in it, but you will get good braking force if it is adjusted correctly, there is a risk that you can leave the adjustment too slack, the lever then fouls the bar and you can have a brown trouser moment. DNAMHIKT either.